Gear chuck



Patented Mar. 18, 1947 y UNITED sTATEs PATENT OFFICE4 GEAR CHUCK `lohn R. Garrison and Ralph P. Garrison, Dayton, Ohio, assignors to Garrison Machine Works, Inc., Dayton, Ohio, a corporation of Ohio Application November 3, 1941, Serial No. sii-17,722 Claims. (Cl. 51-237) This invention pertains to precision work holdcharacteristics and effectivev mode of operation ers or supports, and more particularly to an autoherein mentioned. matically centering chuck or fixture for tem- With the above primary and other incidental porarily holding elongated work parts and maobjects in view as will more fully appear in the chine elements in axially aligned position during 5 specication, the invention intended to be properformance of machining operations thereon. tected by Letters 'Patent consists of the features For illustrat1ve purposes, but with no intent of construction, the parts and eeinhinai'fwns to unduly restrict or limit the scope of the inven- Y thereof, and the mode of operation, or their tion or its application, it is herein shown and deequivalents, as hereinafter described 0r illusscribed as embodied in a duplex gear chuck for 1o trated in the accompanying drawings. bevel gear clusters, wherein the work part is In the aeeenlpenying drawings, Whelein is accurately located for cylindrical grinding or illustrated the preferred but obviously not necesother precision operation, by the pitch lines of sarly the only form of embodiment of the inrelatively spaced gear pinions or by the pitch VentiOn, line of one gear and a distant axially aligned cen- Figs 1' and la al'e perspective Views of the c0- ter. The work holder or chuck is adapted to be Operative Darts of a chuck or work holder emused between centers of a cylindrical grinder, bodying the present invention, separated One where it insures that all cylindrical surfaces and from the other, preparatory to receiving the Work shoulders will be ground concentric with each Darother and with the pitch line of the gear, and 2o Fia 2 is a perspective View 0f a duplex pinion that all other finished surfaces shall be accumember engageable in the chuck or work'hc'lder rately formed in relation to the axis of the part. shown in Figs. l and la.

It is to be understood, however, that the in- Fig. 3 is a longitudinal sectional view of the vention is not limited t0 the specic disclosure, chuck or work ho-lder assembled with the duplex but when constructed in commensurate sizes and pinion member therein.

proportions may be adapted for support of spiral Fig. 4 is a side elevation, partly in section, illusand spur gear units and machine elements of trating the adaptation of the invention to a maother character and different forms. chine element, whei ein a gear and shaft are cenconstruction of work holders and automatic cenaligned with a distant axial center of the work tering fixtures, whereby they may not only be element.

economically manufactured, but will be more ein- Fig. 5 is a detail View of a modication.

cient in use, possess maximum accuracy, be au- Like parts are indicated by similar characters tomatic in operation of centering and aligning of reference throughout the several views.

and engaged part, uniform in operation to en- The Chuck assembly, as shOWnn Figs. l, la and repair, sarily identical with the gear chuck forming the A further Object of the invention is to provide subject matter of Letters Patent No. 2,153,829, chuck of the character mentioned which is issued April ,11) 1939' These Chuckvbodes are adapted for quick and easy insertion and refmgageable Wlth a duplex. gear element cmpriS moval of the work parts and which will autoing spaced-beve1 gear pmlons 2"'2 which are matically center and axially align the inserted element' 45 faces 4, in which are disposed a series of inclined machining and finishing operations circumferentially spaced pairs of geal teeth of the A further object of the invention is to provide pinions 2, accurately on the pitch circles thereof. the herein described method of centering and Obviously, if the machine elements to be loaligning machine elements. cated in the chuck or xture embody other forms A further object of the invention is to provide of gear pinions, or other shapes of shafts, hubs a Work holding chuck having the advantageous or extensions, the chuck bodies l will be correstructural features and inherent meritorious 55 spondingly designed to conform thereto.v A

i enlarged abutment head 1 and formed integral therewith. rlhe arbor d with its stud Il.

:2,417,409 i i i 1 The chuck bodies l--la are mounted in spaced arbor or mandrel E, having an S are quite accurately machined and finished, as are also the chuck heads. These parts are manufactured with such precision that the chuck bodies are held exactly parallel with each other and with their axes exactly aligned and with the gear locating pins 5, or other gear engaging elements, in an series.

The chuck bodies l-la the arbor with other chuck bodies of diierent size,

or adapted for engagement with work bodies oil other types. The integral arbor head iis cona terminal hub 8 accurately concentric are interchangeable on Y Y Y Y and all other nected with one of the chuck vbodies for unison rotation by a driving pin or stud 9 carried by one member and having engagement in a corresponding hole in the other member. The chuck body la at the opposite end of the arbor is removable to enable placement and removal of the work member 23. The latter chuck body ia is mount ed on a bushing or thimble H3 engageable over the arbor spindle 6, and with which it is engaged for unison rotary and axial adjustment by a screw Screw threaded upon the end of the arbor 6 is a recessed thrust collar i2, which is recessed at i3 to receive the head M of the bushing or thimble I0. The latter is perpherally rabbeted at l5, forming an annular shoulder which is overhung by a radial stud l5 carried by the thrust collar l2. The thrust collar is formed with a central hub il which projects within a counterbore in the head lll of the bushing Ill and exerts axial pressure thereon upon tightening adjustment of the collar. Upon retraction of the collar I2, the overhanging stud i6 by engagement with the peripheral shoulder of the bushing head lll exerts retractive influence upon the bushing and upon the gear chuck la connected thereto, to release the engaged work part. The inner end of the bushingl@ is beveled at I8 for automatic `centering thrust engagement with the end of the work part in the event that it does not include a gear element engageable with the chuck. In such event, the gear ly removed and the l! may be relied upon as illustrated in Fig. 4. For this purpose the terminal of the sleeve Ml may be either exteriorly or interiorly beveled to agree with the end of the work part to be engaged thereby.

thrust o the tapered sleeve The chuck body and associated bushing sleeve IB having been removed from the arbor as in Fig. la, the work piece is telescopically thrust over the arbor or mandrel 6 and the chuck assembly, Fig. la, is restored, and the thrust `collar Il! is engaged with the arbor. By tightening the thrust collar l2 upon the screw threaded eXtrernityof the arbor, the work part is pressed longitudinally against the chuck body ,l to cause the locating pins of the latter to engage between the teeth of the pinion 2.V The same thrust action of the collar l2 .likewise presses the chuck body la against the opposite pinion 2 Yof the work part, forcing. the locating pins of the chuck bodyinto automatic centering relation with the engaged pinion o the work part. As before stated, the 4locating pins or studs of the respective chuck bodies are quite accurately shaped and positioned to engage the respective gear pinions upon the pitch lines thereof.

Such chucks are so gear pinions only in designed `as to supp-ort the chuck body ia may be entireto center the work part,

Y or less specicas to adapted to be mounted upon centers of` a machine Y tool, such as a cylindrical grinder or other shaping or finishing machine. Even though the gear pinions 2 be not initially concentric with the intermediate shaft portion 3, when finished they will be accurately reformed to suchrelationship surfaces brought into concentricity with the pitch circles of the gear pinions. f

In the event that the work part is elongated but devoid of a sec-ond gear pinion, the sleeve il) cooperates with the chuck body at thereof to axially align the Work member. Inasmuch as machine elements which necessitate accurately centered and axially aligned iinished surfaces are of great variety of shapes and sizes, the chuck assemblies therefor must necessarily comprise many different shapes and sizes, which, however, embody the same dominant features and characteristics and operate in the sainel manner as that illustrated and described herein.

Many gear elements for which arbor type chucks are required have a gear body at one end only. Some times such gear elements lack either chambers or hubs as shown in the drawings or having either a chamber or ahub it may be unwise to use such feature as a locating means since it may prevent the gear seating accurately upon the chuck at the opposite end of the element. Such condition may result from distortion incident to hardening or to inaccurate machining. inasmuch as the pitch circle of the gear body is the accepted basic or controlling factor and all finishing operations are performed concentric therewith, it is sometimes desirable to provide thrust pressure necessary to seat the gear body solidly upon the chuck without necessarily exerting any centering or locating influence.

This may be eiected by a clamp nut on the threaded end of the arbor .having a loose or sloppy fit, but `is preferably effected by a float-Y ing thrust collar such as that shown at Illa in Figure 5. The collar la abuts against the end of the gear element, but being capable `or limited wobble movement it readily accommodates itself to misalignment of the gear element being Y chucked.. In such instance the thrust sleeve l0 may be looselyengaged therewith for relative rotary motion of the sleeve l and thrust collar lea by a stud i9 engaging .in a Vperipheral groove 2d of the thrust collar, Vwhich is thus free for any necessary movement in tclaskew position.

From the above description it will be apparent thatV there is thus provided a device Aof the char- Y g the particular features of advantage beioreenumerated as desirable, but

which obviously is susceptible of modificationin Y its form, proportions, detail constructionandgarrangementoi partswithout departing froml the principle involved or sacrificing any 'of ritsmadvantages. f

While in order to comply with-the statute, the invention has been Vdescribed in'languagemore structural features, iteisto be understood that the invention is not limited to the specific features shown, and construction but that themeans herein disclosed comprise` the Iaccurate concentricrelation preferred form of several modes of putting theV the opposite end invention into eiect, and the invention is there- Ll. In a work holder, a mandrel having a screw fore claimed in any of its forms or modications threaded extremity, a stop collar on the mandrel within the legitimate and valid scope of the apin spaced relation with its threaded extremity, a pended claims. work chuck mounted on the mandrel in abutting Having thus described our invention, we claim: relation with the stop collar, a second Work engageable with the teeth of an interposed duplex for one of the chucks projecting beyond the face which one of the chucks abuts, a thrustI collar l5 and out of engaging relation with a work part screw threaded upon the arbor in abutting relainterposed therebetween.

tion with the other gear chuck for relatively ad- 5. In an automatically centering chuck for a justing the gear chucks to clamp the interposed duplex gear element, an arbor, a pair of gear duplex gear therebetween. chucks disposed thereon in spaced axially aligned 2. A work holder, including an arbor, a pair opposed relation with each other, having porof gear chucks mounted thereon for axial adjusttions thereon for interlocking engagement with ment of one relative to the other, locating projecthe teeth of an interposed double faced gear eletions upon the adjacent faces of the gear chucks ment, and clamp means engageable with the-arbor for engagement with the teeth of an interposed for axially adjusting the gear chucks into clampgear element, a bushing sleeve in one of the ing engagement with the interposed gear elechucks having a tapered extremity projecting ment.

beyond the face of the chuck, the chuck and JOI-IN R. GARRISON. tapered bushing being selectively engageable with RALPH P, GARRISON, an interposed gear element one to the exclusion of the other, and adjusting means common to the REFERENCES CITED chuck and tapered bushing for effecting thrust The following references are of record in the engagement of the selected member with a gear me of this patent: element interposed between the gear chucks.

3. In a Work holder, a gear chuck, locating UNITED STATES PATENTS members carried thereby for engagement with Number Name Date a Work piece, a mounting therefor including a 1,354,513 McGrady Apr- 19 1932 bushing sleeve for the chuck having a tapered A 118731752 Fraser Aug 231 1932 extremity projecting beyond the face of the 1,937,726 Stel-ner De@ 5, 1933 chuck, the chuck and the tapered bushing sleeve 219395711 Einstein May 5) 1936 being selectively engageable with a work piece, 2,110,931 Dyer et a1 Man 15, 1933 and a thrust member common to the gear chuck 149,929 Henry Apr. 21, 1874 and the tapered bushing sleeve operative to axi- 1,993,919 B911 et a1 Apr; 23J 1935 ally adjust the selected one thereof into engage- $97,937 ,Smau Selm 8, 1998 ment with a work piece. 1,036,994 carving 25:12:: Aug. 27, 1912 

